Everyone who hasn't been living under a rock in the last ten years, knows the true risk of browsing through the dark corners of the web: Pesky Browser-Toolbars, just waiting to infest your PC with superfluous functionality and unwanted UI-cluttering. And as if stealthily installing themselves wasn't enough, some of them may even refuse to be deinstalled in the Add-on section of Firefox. This can get particularly annoying when they start affecting the performance of your browser, cause crashes or simply get on your nerves for making Firefox look untidy.

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That's why in this How-To we show you how to not only completely wipe Firefox-extensions like toolbars from your Browser menu, but also Firefox plug-ins, such as software like Adobe Acrobat, Shockwave Flash or Quicktime, which is often drawn to conflicts and crashes. Normally, these plug-ins are easily deletable via the control panel of Windows, but if that doesn't work, try out one of our tips:   

How to delete Extensions in Firefox:

First, check your Add-ons-section in Firefox. You can find it by going over Firefox > Add-ons > Extensions. In the best case, the button to remove a particular extension is present and clickable on the right side. If so, simply click on it and your extension should be removed without further complications. If the button is greyed out, the Browser might need to be restarted in safe mode first by going over Firefox > Help > Restart Firefox with Add-ons Disabled.

If this doesn't work either or the "Remove"-button wasn't present to begin with, things get a little more complicated. To uninstall extensions manually, they need to be removed directly from the folder where they were installed. To nagivate there, open your "Profile"-window by going over Firefox > Help > Troubleshooting information. Under the "Application Basics"-section, click on the Button "Show Folder" to open your user data folder for Firefox. Most of your extensions XPI-files can be found here in the "extensions"-folder, though some of them may create additional folders outside of it as well.

As most names for files and folders are usually held in the form of ID-columns, they are often rather cryptic and uninterpretable. To find out which extension corresponds to which folder, return to the "Troubleshooting Information"-tab, scroll the the "Extensions"-section and compare the ID-string for each extension with the names of the folders or XPI-files. After identifying the extension you are looking for, simply delete the file or folder to be rid of it.

Alternatively, some extensions may also be installed globally, so that they don't confine to just your own profile folder. Such extensions can normally be found in the installation folder of Firefox itself (typically C:\Program Files (x86)\Mozilla Firefox\extensions). Otherwise, there's not much different about them. Just follow the same steps as above to delete them.

How to delete Plug-ins in Firefox:

A list of all the plug-ins that are currently installed in Firefox can be found right next to the Extensions-section, under Firefox > Add-ons > Plug-ins. And in keeping with tradition, plug-ins normally can't be deleted from the Browser-UI either. Be sure to check the control panel of Windows first to find out whether or not they can simply be uninstalled there, before bothering with the manual removal. If not, open a new tab in Firefox and enter "about:config" to bring up a list of configuration entries for Firefox. Type "plugin.expose_full_path" into the search field and click on the corresponding entry in the list to change its boolean value from "false" to "true".

By doing so, Firefox is allowed to display the complete installation path of all its plug-ins in the configuration-window. To open the latter, simply type "about:plugins" into the browser address bar and hit enter. You should now be able to see all installed plug-ins and their according file paths neatly summed up in a compact list. To remove a particular plug-in from Firefox, simply track its installation path and delete or rename the DLL-file.